Impeller assembly for use in an aquarium filter pump and methods

ABSTRACT

An impeller for use in an aquarium filter pump includes a shaft and a plurality of impeller blades radially extending from the shaft. Each of the impeller blades includes opposite blade faces. A depression is in each of the blade faces and aids in pushing the water. The depression can be a variety of shapes and can have its deepest portion along one of the edges of the blade.

TECHNICAL FIELD

This disclosure relates generally to devices and methods for filteringaquarium water. More specifically, this disclosure relates to animproved impeller for use an aquarium filter pump.

BACKGROUND

To maintain an ecological balance within an aquarium, it is necessary tokeep the water in the aquarium clean. Cleaning is often accomplished bypumping water from the aquarium to a filter device. The filter devicewill clean the water by having it pass through a filter medium, and thenthe cleaned water is returned to the aquarium. Such filtering devicesgenerally include an internal pump driven by an electric motor forpumping the water through the filter medium. Improvements are desirableby increasing the flow rates through the pump, without increasing theimpeller size to allow for compact impeller designs.

SUMMARY

An impeller for use in an aquarium filter pump that improves the priorart is provided.

An impeller includes a shaft and a plurality of impeller blades radiallyextending from the shaft. Each of the impeller blades includes oppositeblades faces; a free edge remote from the shaft; first and secondopposite edges extending from the shaft to the free edge, wherein theblade faces are bordered by the first and second edges and the freeedge; and a depression in each of the blade faces. The depression is ata maximum depth within the respective blade face at one of the edges.

In example embodiments, the shaft has a longitudinal axis, and eachblade is along a plane containing the first and second edges. Each planealso contains the longitudinal axis of the shaft.

In many examples, the free edge, first edge, and second edge, arestraight edges.

In some embodiments, the depression has a periphery with a shape of twoopposite mirrored sections that round to a vertex region.

In examples of depressions that have a vertex region, in someimplementations, the vertex region is adjacent to the shaft, and thefree edge is a deepest portion of the depression.

In some implementations, the depression has a periphery forming a curvedshaped with a vertex region adjacent the first edge, and the second edgeis a deepest portion of the depression.

For some embodiments, the depression increases in depth as thedepression extends from adjacent the shaft to the free edge.

In some embodiments, there are no more than four blades.

In some embodiments, there are at least three blades and no more thanfour blades.

In another aspect, an impeller assembly for use in an aquarium filterpump is provided. The impeller assembly includes a shaft with alongitudinal axis, a rotor mounted on the shaft, and an impeller mountedon the shaft. The impeller has at least three blades radially extendingfrom the shaft. Each blade is along a plane containing the longitudinalaxis of the shaft. Each blade has an opposite blade face. Each blade hasstraight, opposite first and second edges extending from the shaft and astraight free edge extending between the first and second edges. Eachblade face has a depression.

In some examples, the depression has a periphery with a shape of twoopposite mirrored sections that round to a vertex region.

In some examples, the vertex region is adjacent to the shaft, and thefree edge is a deepest portion of the depression.

In some examples, the depression has a periphery forming a curved shapedwith a vertex region adjacent the first edge, and the second edge is adeepest portion of the depression.

In some implementations, the depression increases in depth as thedepression extends from adjacent the shaft to the free edge.

In another aspect, a method of pumping water for an aquarium filter isprovided. The method includes rotating an impeller in an aquarium todraw water into the filter. The step of rotating the impeller includesrotating blades. Each blade includes opposite blade faces; a free edge;first and second opposite edges, with the blade faces being bordered bythe first and second edges and the free edge; and a depression in eachof the blade faces. The depressions aid in pushing the water.

A variety of additions aspects will be set forth in the description thatfollows. The aspects can relate to individual features and tocombinations of features. It is to be understood that both the foregoinggeneral description and the following detailed description are exemplaryand explanatory only and are not restrictive of the broad inventiveconcepts upon which the examples disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a filter assembly for use with anaquarium having a pump, according to principles of this disclosure;

FIG. 2 is a front top perspective view of the pump assembly used in thefilter assembly of FIG. 1, with portions removed for visibility, andshowing an impeller assembly, constructed in accordance with principlesof this disclosure;

FIG. 3 is a perspective view of a first embodiment of an impeller usablein the pump assembly of FIG. 2, constructed in accordance withprinciples of this disclosure;

FIG. 4 is an enlarged view of a portion of the impeller of FIG. 3;

FIG. 5 is a front view of the impeller of FIG. 3;

FIG. 6 is an enlarged view of portions 6-6 of FIG. 5;

FIG. 7 is a perspective view of a second embodiment of an impellerusable in the pump assembly of FIG. 2, constructed in accordance withprinciples of this disclosure;

FIG. 8 is a top view of the impeller of FIG. 7;

FIG. 9 is a front view of the impeller of FIG. 7;

FIG. 10 is a bottom view of the impeller of FIG. 7;

FIG. 11 one of the blades shown at portion A of FIG. 10;

FIG. 12 is a perspective view of a third embodiment of an impellerusable with the pump assembly of FIG. 2;

FIG. 13 is a front view of the impeller of FIG. 12;

FIG. 14 is an enlarged view of portion B of FIG. 13; and

FIG. 15 is a cross-sectional view of the impeller of FIG. 12.

DETAILED DESCRIPTION

Various examples will be described in detail with reference to thedrawings, wherein like reference numerals represent like parts andassemblies throughout the several views. Reference to various examplesdoes not limit the scope of the claims attached hereto. Additionally,any examples set forth in this specification are not intended to belimiting and merely set forth some of the many possible examples for theappended claims. In the drawings, like reference numbers correspond tolike or similar components throughout the several figures.

A. General Overview

FIG. 1 illustrates a filter assembly 20 usable with an aquarium in orderto clean the water in an aquarium. The filter assembly 20 includes afilter housing 22, an intake tube assembly 24 and a pump assembly 26.When the pump assembly 26 is activated, water is drawn by the pumpassembly 26 from an aquarium, through the intake tube assembly 24. Thewater is then moved through the pump assembly 26 and into the internalfilter assembly components (not shown). The internal filter componentsclean the water and return the filter water back to the aquarium.

FIG. 2 illustrates the pump assembly 26 with housing parts removed toshow internal components. The pump assembly 26 includes an impellerassembly 30. The impeller assembly 30 includes a rotor 32 mounted on ashaft 34. Impeller 36 is also mounted on the shaft 34.

In general, when the pump motor (not shown) operates, a magnet attachedto the rotor spins. This also causes the shaft 34 to spin, which spinsthe impeller 36. The spinning impeller 36 pushes water, which drawswater in to the pump assembly 36 by drawing it through the intake tubeassembly 24 from the aquarium.

B. Example First Embodiment of Impeller, FIGS. 3-6

A first example embodiment of impeller 36 is shown in FIGS. 3-6. Theimpeller 36 has shaft 34. The shaft 34 defines a longitudinal axis 38.In general, the impeller 36 rotates or spins about the axis 38, which isan axis of rotation.

The impeller 36 includes a plurality of impeller blades 40. While thereshould be at least two blades 40, there are typically no more than sixblades. In this embodiment, there are four blades 40. The blades 40radially extend from the shaft 34. In general, the blades 40 are locatedadjacent an end 42 of the shaft 34 opposite from a holding location 44for the rotor 32.

Each of the blades 40 includes opposite blade faces 46, 47. In thisembodiment, the blade faces 46, 47 are identical. In alternativearrangements, the faces 46, 47 would not need to be identical.

Each of the blades 40 includes a free edge 50. The free edge 50 isremote from the shaft 34 and joins the faces 46, 47. In this embodiment,the free edge 50 is straight and generally parallels the longitudinalaxis 38 of the shaft 34.

Each of the blades 40 includes a first edge 52 extending from the shaft34 to the free edge 50. Opposite of the first edge 52 is a second edge54 extending from the shaft 34 to the free edge 50. In this embodiment,the first edge 52 and second edge 54 are generally straight and parallelto each other. The first edge 52 and second edge 54 are also generallyperpendicular to the central axis 38 of the shaft 34.

By reviewing FIGS. 3 and 4, it can be appreciated that each of the bladefaces 46, 47 are bordered by the first and second edges 52, 54 and thefree edge 50.

In accordance with principles of this disclosure, each of the bladefaces 46, 47 includes at least one depression 60. The depressions 60provide an advantage over impellers that do not have blades withdepressions. For example, the depressions 60 in the blades 40 provideincreased flow rates over conventional flat blade impellers. Thedepressions 60 increase the water volume pushed by the blades 40, whichresults in a greater flow rate over conventional flat blades. Thisallows for increased flow rates without increasing the impeller size,which allows for compact impeller designs.

In general, the depression 60 in each of the blade faces 46, 47 has amaximum depth along one of the edges 50, 52, 54. The deepest portion ofthe depression 60 is also the location on the blade face 46, 47 that isthe thinnest portion of the respective face 46, 47.

In the embodiment of FIGS. 3-6, the free edge 50 is the deepest portionof the depression 60. This can be seen in, for example, FIG. 6, whichshows an end view of one of the blades 40, and the free edge 50 isvisible in plan view. The depression 60 can be seen as curving from anarea of largest depth adjacent the first edge 52 and second edge 54 to amiddle section 62 halfway between the first edge 52 and second edge 54and along the free edge 50. This middle section 52 is also the deepestportion of the depression 60.

In the embodiment of FIGS. 3-6, the depression 60 has an outer peripherywith a shape of two opposite mirrored sections 64, 65 which then extendtoward each other until ending at a vertex portion or region 68. Theperiphery of the depression 60 can generally round from the mirroredsections 64, 65 and end at the vertex region 68, which can be a roundedsection or a sharp point. The vertex region 68 is adjacent to the shaft34, while the mirrored sections 64, 65 are adjacent to the first andsecond edges 52, 54. The free edge 50 is the deepest part of thedepression and halfway between the mirrored sections 64, 65.

C. Example Second Embodiment of Impeller, FIGS. 7-11

FIGS. 7-11 illustrate a second embodiment of impeller 36. Similarreference numbers have similar parts as the first embodiment, and adescription of those parts is not repeated here but is incorporatedherein by reference.

In this embodiment, there are three blades 40.

In this embodiment, the depression 60 has a maximum depth along thesecond edge 54. The depression 60 has a periphery forming a curved shape70 with a vertex portion 72. The vertex portion 72 is adjacent the firstedge 52, while the second edge 54 is a deepest portion of the depression60. In FIG. 11, the second edge 54 is shown in plan view. The deepestportion 74 of the depression 60 can be seen to be halfway between thefree edge 50 and where the blade 40 secures to a remaining portion ofthe impeller 36 at the shaft 34. In general, in this embodiment, thecurved shaped 70 can be viewed as parabolic; or generally a section(such as a half or quarter section) of an oval.

D. Example Third Embodiment of Impeller, FIGS. 12-15

FIGS. 12-15 illustrate a third embodiment of impeller 36. Again, likenumbers represent like parts, and the descriptions of those parts arenot repeated here but are incorporated herein by reference.

In this embodiment, there are four blades 40. The depression 60 in eachof the blade faces 46, 47 increases in depth as the depression 60extends from adjacent the shaft 34 to the free edge 50. In other words,the blades 40 are thickest along the region adjacent to the shaft 34 andare thinnest along the free edge 50. In between the free edge 50 and theshaft 34, the blades gradually increase in thickness. This results inthe depression 60 having the greatest depth along the free edge 50 ascan be seen in FIG. 15.

In this embodiment, the overall free edge 50 forms the cross section inthe shape of an I, since the first edge 52 and second edge 54 protrudeoutwardly beyond the faces 46, 47 at the regions of depression 60.

E. Example Method

The impeller assembly 30 can be used as part of a method of pumpingwater for an aquarium filter. The method includes rotating the impeller36 in an aquarium to draw water into the filter. The step of rotatingthe impeller 36 includes rotating blades 40. Each blade 40 includesopposite blade faces 46, 47. Each of the blade faces 46, 47 hasdepression 60, in which the depression 60 aids in pushing the water.

The above represents example principles. Many embodiments can be madeusing these principles.

I claim:
 1. An impeller for use in an aquarium filter pump; the impellercomprising: (a) a shaft; and (b) a plurality of impeller blades radiallyextending from the shaft; each of the impeller blades including: (i)opposite blade faces; (ii) a free edge remote from the shaft; (iii)first and second opposite edges extending from the shaft to the freeedge; the blade faces being bordered by the first and second edges andthe free edge; (iii) a depression in each of the blade faces; thedepression being at maximum depth within the respective blade face atone of the edges; the maximum depth being a thinnest portion of theblade faces.
 2. The impeller of claim 1 wherein: (a) the shaft has alongitudinal axis; (b) each blade is along a plane containing the firstand second edges; and each plane also contains the longitudinal axis ofthe shaft.
 3. The impeller of claim 2 wherein the free edge, first edge,and second edge are straight edges.
 4. The impeller of claim 3 whereinthe depression has a periphery with a shape of two opposite parallelsections that round to a vertex portion.
 5. The impeller of claim 4wherein the vertex portion is adjacent the shaft, and the free edge is adeepest portion of the depression.
 6. The impeller of claim 3 whereinthe depression has a periphery forming a curved shaped with a vertexportion adjacent the first edge, and the second edge is a deepestportion of the depression.
 7. The impeller of claim 3 wherein thedepression increases in depth as the depression extends from adjacentthe shaft to the free edge.
 8. The impeller of claim 3 wherein there areno more than 4 blades.
 9. The impeller of claim 3 wherein there are atleast 3 blades and no more than 4 blades.
 10. An impeller assembly foruse in an aquarium filter pump; the impeller assembly comprising: (a) ashaft with a longitudinal axis; (b) a rotor mounted on the shaft; and(c) an impeller mounted on the shaft; the impeller having at least 3blades radially extending from the shaft; (i) each blade being along aplane containing the longitudinal axis of the shaft; (ii) each bladehaving an opposite blade face; (iii) each blade having straight,opposite first and second edges extending from the shaft and a straightfree edge extending between the first and second edges; (iv) each bladeface having a depression and being at a thinnest portion of the bladefaces; and (v) the depression having a periphery with a shape of twoopposite parallel sections that round to a vertex.
 11. The impellerassembly of claim 10 wherein the vertex is adjacent the shaft, and thefree edge is a deepest portion of the depression.
 12. The impellerassembly of claim 10 wherein the vertex is adjacent the first edge, andthe second edge is a deepest portion of the depression.
 13. The impellerassembly of claim 10 wherein the depression increases in depth as thedepression extends from adjacent the shaft to the free edge.
 14. Amethod of pumping water for an aquarium filter, the method comprising:(a) rotating an impeller in an aquarium to draw water into the filter;(b) wherein the step of rotating the impeller includes rotating blades,each blade including: (i) opposite blade faces; (ii) a free edge; (iii)first and second opposite edges; the blade faces being bordered by thefirst and second edges and the free edge; (iii) a depression in each ofthe blade faces; the depression increasing in depth within therespective blade face as the depression extends to one of the edges; amaximum depression depth being a thinnest portion of the blade faces;and wherein the depressions aid in pushing the water.